1. Field of the Invention
The present invention relates to an optical waveguide switch, which is formed on optical waveguides for optical signal transmission to perform optical signal switching or translation and the like, and also a method of manufacturing the optical waveguide switch.
2. Description of the Related Art
Various digital electronic apparatuses such as personal computers, mobile phones, video apparatuses and audio apparatuses, for instance, are mounted with a large number of integrated circuit elements such as various kinds of Integrated Circuit (IC) elements, Large Scale Integration (LSI) elements and memory elements. In the integrated circuit elements, efforts have been made to attain increased functionality, multi-functionality, increased speed processing with sharply increasing operation speed, etc.,in addition to form-factor reductions such as size, weight and thickness with micro-fabrication of interconnect patterns, downsizing of IC packages, rapid progress of integration scales, implementation of multi-pinning or improvement of packaging methods such as packaging technologies of chip size package (CSP).
Signal transmission in integrated circuit elements and the like, including relatively short-distance signal transmission such as transmission between intra-board integrated circuit elements, for instance, takes place typically with electrical signals transmitted through electrical interconnects. In the signal transmission, efforts are being made to further increase a transmission performance in consideration of needs of increased speed transmission of information signals, increased density of signal patterns and the like in the future. However, an approach to an increased transmission performance with electrical interconnects has transmission performance limitations. Specifically, the signal transmission with the electrical interconnects needs to take measures against intra-interconnect pattern problems such as delayed signal transmission with a Capacitance Resistance (CR) time constant, Electromagnetic Interference (EMI) noise and Electromagnetic Compatibility (EMC) or problems such as inter-interconnect pattern crosstalk and so on.
In the signal transmission, the use of optical signal transmission with an optical interconnect technology realized with optical interconnects, optical interconnections or the like has been noted to settle the above electrical signal transmission problems attributable to the electrical interconnects. The optical signal transmission may ensure that transmission of information signals and the like between apparatuses, intra-apparatus boards or intra-board integrated circuit elements is attainable at high speed. Particularly, in the short-distance transmission such as inter-integrated circuit element transmission, for instance, the optical signal transmission forms an optical waveguide formed on a substrate with the integrated circuit elements packaged to attain high-speed large-capacity optical signal transmission with the optical waveguide as a transmission line, and thus enables suitable building of a transmission system for the information signals and the like to be attained.
For the above optical signal transmission, the various electronic apparatuses, etc. need to be mounted on a hybrid circuit substrate with electrical and optical interconnects embedded together. The hybrid circuit substrate employs a substrate such as a silicon substrate and a glass substrate, for instance, having a surface obtained by planarization. The hybrid circuit substrate has, on a surface thereof, an optical waveguide together with accurate micro-fabricated multi-thin layered electrical interconnect patterns. In the optical waveguide, a photoconductive resin material that is applicable to a low temperature process for patterning with a photolithography, for instance, is suitably used as a material for forming of the optical waveguide.